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espanolDiversos avistamientos de diferentes especies de pinnipedos han sido registrados fuera de sus habituales areas de distribucion. En mayo de 2019, se avistaron, en 4 ocasiones, pinnipedos de aproximadamente un ano de edad en la costa central de Oaxaca, Mexico. Uno de los individuos se encontro herido en la localidad de La Escobilla (Oaxaca, Mexico) y fue trasladado inmediatamente al Centro Mexicano de la Tortuga para su rehabilitacion. La identificacion visual de la especie fue inconclusa debido a que los individuos juveniles de diversas especies de lobo fino pueden ser muy parecidos. Por lo tanto, se realizo un analisis molecular para confirmar la especie. Se extrajo ADN del individuo y se secuencio un fragmento de la region control del ADN mitocondrial. La secuencia del ADN se alineo junto con secuencias de otras especies de lobo fino. Se realizo un analisis de parsimonia, y el arbol confirmo que el individuo era un lobo fino de Galapagos, Arctocephalus galapagoensis. Este es el primer registro de la especie en la costa central de Oaxaca. La presencia atipica de esta especie en el pais podria estar relacionada con altas temperaturas superficiales del mar causadas por eventos como El Nino. EnglishSeveral sightings of different pinniped species have been recorded outside their typical areas of distribution. In May 2019, pinniped yearlings were sighted on 4 occasions on the central coast of Oaxaca, Mexico. One of them was found injured in La Escobilla (Oaxaca, Mexico) and was transported immediately to the Centro Mexicano de la Tortuga for rehabilitation. Visual identification of the species was inconclusive, as young individuals of several fur seal species can be very similar. A molecular analysis was thus performed to confirm the species. DNA was extracted from the individual, and a fragment of the mitochondrial DNA control region was sequenced and aligned with several sequences of other fur seal species. A parsimony analysis was performed, and the tree revealed that the individual was a Galapagos fur seal, Arctocephalus galapagoensis. This is the first record of this species on the central coast of Oaxaca. The atypical presence of this species in the country could be related to high sea surface temperatures associated with events such as El Nino.

We present the annual cycles of the monthly surface and advective heat fluxes from La Boquilla and Tangolunda, two points in the western margin of the Gulf of Tehuantepec. Computations are function of averaged (2011–2013) daily seawater temperature at 5 m depth, interpolated daily SST satellite and daily meteorological data except cloud cover, estimated from ICOADS. The advective heat flux is a result of the imbalance between the net surface heat flux and the heat content rate of change in a 25 m depth water column. Most of the meteorological variables and heat fluxes, show intra-seasonal variability related to the cloud cover that accompanies the Intertropical Convergence Zone position relative to the study area. The latent heat flux, calculated using two distinct exchange coefficients, according to Bunker and to Liu, and the long wave heat flux, are about the same magnitude in each site. In all the computations, the net surface heat flux is positive throughout the year (into the ocean) and correspondingly there is an exportation of advective heat flux along the year from the water column. Large advective heat losses, in February and October, occur when measured southeastward currents are strong. Small losses occur, in May and January, when currents are weak and towards different directions. Currents arriving to the area from the west, seem correspond to mixed water from the tropical Pacific off central Mexico in February. In October, however, similar currents seem to be part of the Costa Rica Coastal Current after leaving the Tehuantepec Bowl. The largest net surface heat flux difference between the two sites (

Background: Sphyrna lewini, is a semi-oceanic and cosmopolitan species globally distributed throughout tropical and warm temperate seas. In the northeastern tropical Pacific, this specie represents an important contribution to the biomass of artisanal and small-scale fisheries. Goals: In this study the aim was to obtain information about length frequency distribution and reproductive aspects of S. lewini, in Oaxaca, Mexico. Methods: Samples were taken from August 2001 to December 2007 in four landing sites of the artisanal fleet on the coast of Oaxaca. Results: Samples were collected 388 females and 434 males. Total length ranged from 44-308 cm for males and from 44-332 cm for females. The catches were made up of neonates (24.3%, 44-74 cm), juveniles (42.2%, 75-170 cm) and adults (33.5%, > 170 cm). The sex ratio shows differences by size, and season. The greatest catches were recorded in the rainy season (85.5%), with a predominance of juveniles and adults, and a higher proportion of males. In the dry season (15.5%) were recorded with a predominance of larger sizes >100 cm in both sexes. The females reached sexual maturity (TL50) at 198.8 cm and the males at 181 cm, based on characteristics and measurements of reproductive organs. A total of 37 gravid females with sizes between 175 and 281 cm were registered, from April to August. Gravid females had between 15-42 embryos, varying from 44-54 cm. Conclusion: S. lewini was present year round in the study area with the greatest catch from April to September, the season when pregnant females were present.

In this study, trophic ecology of Octopus hubbsorum (Berry, 1953) was examined in relation to the species life cycle and dry and rainy seasons. A total of 184 individuals were obtained from the commercial artisanal catches at different localities along the coast of Oaxaca, Mexican tropical Pacific, from January 2011 to December 2012. Analysis of digestive tract contents revealed that O. hubbsorum preyed upon 43 different prey species belonging to five zoological groups (Crustacean, Mollusca, Teleostei, Echinodermata and Polychaeta), cannibalism was only occasional. The most important prey was the porcelain crabs genus Petrolisthes, contributing 52.1% and 37.8% to the total Index of Relative Importance, in females and males, respectively. Dietary comparison between different maturity stages revealed significant changes in the diet with maturation. The proportion of empty stomachs observed between the dry (18.75 %) and rainy (12.5 %) seasons did not differ significantly (χ2 = 0.55, P > 0.05). Our results suggest that females likely migrate to shallow areas to feed in preparation for mating, they may do this to increase energy intake prior to egg caring and incubation, a period when they do not feed. The high productivity waters along the coast of Oaxaca seem to be important to the survival of this species because they offer key food resources at a critical reproductive stage.

This study used multi-scale models to evaluate spatial variation in the structure of the assemblage and functional groups of gastropods associated with hermatypic corals of the Mexican Tropical Pacific. A geographic model examined the spatial scales of the region, geographic position and sites, while an oceanographic model considered the oceanographic characteristics and sites. The relationship between gastropods and environmental and spatial variables was analyzed with additive partitions, based on canonical correspondence analysis. Both models coincide in that the greatest variation of gastropods was presented at quadrant (i.e., small-scale) and site (i.e., local-scale) levels, and the lowest variation to the scale of geographic position and oceanographic characteristics (i.e., medium-scale). Abundance and Shannon diversity presented greater variation at small and local-scales, while species richness presented greater variation at medium-scale. The functional groups varied to the greatest extent at medium-scale in the geographic model and at local-scale in the oceanographic model. The highest abundance, richness and diversity were found at: (1) Plataforma Pavonas and Tunel Amarradero, ~20°N (Northern region), influenced by the California Current and the Mexican Coastal Current; (2) Caleta de Chon and Morro Potosi, ~17°N (Southern region), affected by the Mexican Warm Pool; and (3) Salchi and Isla Montosa, where relatively high biological productivity occur mainly due to coastal upwelling, ~15°N (Southern region). The carnivorous epifauna was the most important functional group at all studied scales. The most important species in both models were the corallivore Coralliophila monodonta, the symbiont Muricopsis zeteki, Triphora hannai of sandy substrate and Vermicularia pellucida eburnea and Engina tabogaensis of hard substrate. Variation among sites was explained mainly by the coverage of sessile taxa (e.g., percentage of coverage of the coral Pocillopora spp., bryozoans, hydrozoans, octocorals and sponges) and proportion of substrates (e.g., sand, rock, dead coral and rubble). However, at upwelling sites, other variables such as primary productivity and phosphate concentration also contributed to local-scale variation. At medium-scale, oceanographic characteristics explain the variation of the assemblage and functional groups of gastropods.

The hydrographic structure and circulation of the Southern Mexican Pacific, from August 31 to September 24 2004, when tropical atmospheric activity was at its peak, was analyzed based on AVISO absolute dynamic topography and an array of 106 CTD profiles, within an area of about 500 km×500 km between Punta Maldonado and Puerto Chiapas. The surveyed area was occupied by mesoscale anticyclonic and cyclonic eddies that determined the path of water with temperature and salinity characteristic of the Costa Rica Coastal Current. The origin of each eddy was investigated with respect to QuikSCAT wind conditions. The sequence of AVISO images and wind data showed that the largest anticyclonic eddies originated outside the Gulf of Tehuantepec through mechanisms distinct from local wind forcing, although two northerly wind events in the Gulf of Tehuantepec possibly had an influence on the smallest anticyclonic and cyclonic eddies. The relative position of each eddy allowed the flow of relatively low temperature and salinity water (the Costa Rica Coastal Current) into and throughout the Gulf of Tehuantepec, converging at about Puerto Angel with relatively high temperature and salinity water moving from the west.

There are many marine protected areas (MPAs) containing coral reef aggregations in the eastern Pacific region. However, the connectivity of corals between MPAs is still poorly known, especially in the Marine Conservation Corridor of the Eastern Tropical Pacific (MCCETP). Here, we assess the potential connectivity of corals across equatorial eastern Pacific MPAs through a Lagrangian particle-tracking algorithm coupled offline with an ocean-circulation numerical model. Connectivity metrics and graph theory were used to analyze the networks and highlight those MPAs that are critical for maintaining the connectivity of corals across the region. Our results show that the equatorial eastern Pacific MPAs form a relatively well-connected network, at least 40% of coral larvae released per year end up within the boundaries of an MPA. MPAs like Malpelo and Gorgona islands included in the MCCETP were found to be critical for connectivity of corals because of their high betweenness centrality and potential role as stepping-stones between coastal MPAs and offshore MPAs such as the Galapagos Islands. Two pelagic larval duration (PLD) scenarios (40 and 130 days) indicate a quasi-unidirectional larval flow from coastal MPAs toward oceanic MPAs, where the only resilient MPAs (Coiba and Malpelo islands) depend mostly on subsidiary recruitment from MPAs located along the coast of Costa Rica, Panama and Colombia. In the two PLD scenarios, Cocos Island maintains a very low resilience potential. Our results indicate the imperative need to include coastal MPAs in the MCCETP network initiative, since connectivity and resilience of coral reefs in the equatorial eastern Pacific region rely heavily on coastal MPAs.

Various authors have suggested that the Islas Marias archipelago, Mexico, may play a significant biogeographic role in the dispersal of Indo Pacific coral species into the Eastern Pacific; however, the coral communities of this archipelago have received scarce attention to date. Here, we first addressed coral community structure across the islands and, by employing ordination analysis, minimum spanning tree and particle-tracking experiments, used this information to evaluate the relevance of the archipelago for coral dispersal. Twenty-four coral communities were recorded in the archipelago. Coral cover varied significantly among islands: Maria Cleofas had large values (38.5%), intermediate values were observed for Maria Madre (26.5%) and Maria Magdalena (22.84%), and relatively low values were recorded for San Juanito (18.5%). Coral communities mainly consisted of Pocillopora (57.3%) and Porites (25.5%) species, while species of Pavona (16%) and Psammocora (0.6%) made relatively minor contributions. Thirteen stony coral species were identified in the archipelago; of these Psammocora profundacella and Pavona duerdeni represent new records. Ordination analysis, minimum spanning tree and particle-tracking experiments suggested similar connecting paths in the studied area; in general, the Islas Marias stands as a route for coral dispersal of Indo Pacific species into the Northeastern Pacific. In a regional context, the Islas Marias has three major biogeographic implications to coral dispersal: (i) the archipelago stands as a major stepping stone for the transport of species and individuals among the Revillagigedo archipelago, the Gulf of California and the tropical Mexican Pacific; (ii) the Islas Marias may play a seminal role in maintaining the genetic connectivity between southern and northern coral populations along the Mexican Pacific and (iii) because of its relatively pristine status and low levels of human impact, the archipelago may potentially serve as a source of coral propagules for ecosystem recovery in the Gulf of California and along the Pacific coast of the Mexican mainland following natural and/or human induced perturbations.

10 páginas, 7 figuras, 2 tablas., A high-resolution (∼1.2 km) 3D numerical model was used to analyze the interaction of the Northern Current (a right-bounded flow) with the Blanes submarine canyon (BC, NW Mediterranean). Although it refers to a climatological simulation the model properly suites our purpose since it simulates the Northern Current (NC) mesoscale variability, as well as its seasonal variability. Model results were validated with satellite sea surface temperature and current-meter data. The simulated NC tends to be faster and deeper in winter, and slower and shallower in summer. According to our results, NC meanders and eddies are recurrent in the BC area and produce highly fluctuating three-dimensional circulation patterns within the canyon. We found that NC meanders and anticyclonic eddies propagating along the current pathway tend to be deep and, consequently, their effects extend down to the deeper part of the BC. We also found that the meandering of the NC plays a key role in enhancing vertical motions inside the BC. Upwelling and downwelling events occurring on timescales of 4–20 days are associated with NC meanders crests and troughs passing over the BC. Net upwelling/downwelling events are accordingly influenced by the NC seasonality. They are more predominant in winter, while damped in summer. Our results show the importance of NC meanders in creating local net upwelling/downwelling and strengthen the evidence that continuous right-bounded (downwelling favorable) flows can also produce net upwelling inside submarine canyons., M.-A. Ahumada-Sempoal was partially supported by PROMEP (Programa para el Mejoramiento del Profesorado, Secretaría de Educación Pública, México) in the framework of a Ph.D. grant. The research project OAMMS (CTM2008-03983) funded by the Spanish Ministry of Science and Innovation provided support for the OOCS Station from 2009 to 2011.

El tiburón piloto Carcharhinus falciformis es una especie oceánica abundante, que se distribuye en zonas ecuatoriales y tropicales, con importante captura en las costas Atlántica y Pacífica de México. De diciembre 2000 a diciembre 2007 se efectuaron muestreos en cuatro sitios de desembarco de la flota artesanal en la costa de Oaxaca. Durante el período de estudio, se registraron 1236 individuos (602 hembras y 634 machos) de C. falciformis. El intervalo de tallas en las hembras varió de 49 a 217 cm LT (media = 111,3 cm) y en machos de 59 a 265 cm de longitud total (LT) (media = 111,7 cm). La proporción sexual macho: hembra fue de 1:1 (χ20.05 = 0.78, P > 0,05). Se estimó una talla de primera madurez sexual de 184,8 cm LT para hembras y 178,5 cm LT para machos. Las capturas estuvieron constituidas principalmente por juveniles. El número promedio de embriones por hembra fue de siete en las 52 hembras preñadas examinadas, con un rango de 3-14 embriones. La LT promedio de los embriones varió de 10 a 66 cm, observándose evidencia de cambios estacionales en la talla. Los resultados obtenidos mostraron que C. falciformis da a luz la mayor parte del año, con una mayor proporción de nacimientos durante la temporada de lluvias (mayo a octubre). Carcharhinus falciformis is an abundant oceanic species, which occurs in equatorial and tropical zones, with an important catch in the Atlantic and Pacific coasts of Mexico. Samples were taken from December 2000 to December 2007 in four landing sites of the artisanal fleet on the coast of Oaxaca. During the period of study 1236 specimens (602 females and 634 males) of C. falciformis were registered. Total length (TL) ranged from 49 to 217 cm for females (mean = 111.3 cm) and from 59 to 265 cm for males (mean = 111.7 cm). The sex ratio of females to males was 1:1 (χ20.05 = 0.78, P > 0.05). The present data suggest a size at first sexual maturity of about 184.8 cm TL for females and 178.5 cm TL for males. The catches were composed mainly of young. In the 52 gravid females examined, the average number of embryos per female was seven; with a range of 3-14 embryos. Mean TL of embryos ranged from 10 to 66 cm with evidence of seasonal changes in the size structure. Results obtained showed that C. falciformis gives birth most of the year, with the highest proportion of births during the rainy season (May to October).

11 páginas, 2 tablas, 6 figuras, A climatological simulation performed with a fine-resolution(∼1.2km) 3D circulation model nested in one-way to a coarse-resolution (∼4 km) 3D regional model is used to examine the cross-shelf break water exchange in the Blanes submarine canyon (∼41°00′–41°46′N; ∼02°24′–03°24′E). ALagrangian particle-tracking model coupled to the fine-resolution 3D circulation model is used to investigate the role of the incident regional flow (i.e.the Northern Current, NC)and its seasonal variability on the dispersion and residence time of passive particles inside Blanes Canyon.The NC flows southwestward, along the slope, with the coastline to th eright.Water is advected offshore/onshore at the upstream/downstream canyon walls, with a net water transport toward the slope (i.e.offshore). The amount of water moved across the shelf break of the upstream wall is approximately three times larger than the amount moved across the shelf break of the downstream wall. This preferential zone for cross-shelf break water ex- change is explained by the asymmetric geometry of the canyon and the orientation of the incident current with respect to the canyon bathymetry. Passive particles released upstream Blanes Canyon be- tween themid-shelf and the upper-slope drift within the NC and accumulate over the shelf edge of the canyon. About half of the particles released at depths above the shelf break move towards shallower areas inside the canyon. In contrast, about two-thirds o fparticles released below the shelf break move to deeper areas.Particle dispersion is higher under weakly (e.g.winter) than strongly (e.g.summer) stra- tified conditions. The residence time of passive particles inside the canyon (∼4–6 days) is double than the residence time downstream of the canyon, indicating that the canyon acts as an efficient retention zone for passive particles., This research was partially carried out at the Jet Pro- pulsion Laboratory, California Institute of Technology, under a contract with th eNational Aeronautics and Space Administration.

26 páginas. 11 figuras,1 tabla.

22 páginas, 8 figuras, 1 tabla., The new pelagic Operational Observatory of the Catalan Sea (OOCS) for the coordinated multisensor measurement of atmospheric and oceanographic conditions has been recently installed (2009) in the Catalan Sea (41°39'N, 2°54'E; Western Mediterranean) and continuously operated (with minor maintenance gaps) until today. This multiparametric platform is moored at 192 m depth, 9.3 km off Blanes harbour (Girona, Spain). It is composed of a buoy holding atmospheric sensors and a set of oceanographic sensors measuring the water conditions over the upper 100 m depth. The station is located close to the head of the Blanes submarine canyon where an important multispecies pelagic and demersal fishery gives the station ecological and economic relevance. The OOCS provides important records on atmospheric and oceanographic conditions, the latter through the measurement of hydrological and biogeochemical parameters, at depths with a time resolution never attained before for this area of the Mediterranean. Twenty four moored sensors and probes operating in a coordinated fashion provide important data on Essential Ocean Variables (EOVs; UNESCO) such as temperature, salinity, pressure, dissolved oxygen, chlorophyll fluorescence, and turbidity. In comparison with other pelagic observatories presently operating in other world areas, OOCS also measures photosynthetic available radiation (PAR) from above the sea surface and at different depths in the upper 50 m. Data are recorded each 30 min and transmitted in real-time to a ground station via GPRS. This time series is published and automatically updated at the frequency of data collection on the official OOCS website (http://www.ceab.csic.es/~oceans). Under development are embedded automated routines for the in situ data treatment and assimilation into numerical models, in order to provide a reliable local marine processing forecast. In this work, our goal is to detail the OOCS multisensor architecture in relation to the coordinated capability for the remote, continuous and prolonged monitoring of atmospheric and oceanographic conditions, including data communication and storage. Accordingly, time series of measurements for a number of biological parameters will be presented for the summer months of 2011. Marine hindcast outputs from the numerical models implemented for simulating the conditions over the study area are shown. The strong changes of atmospheric conditions recorded in the last years over the area have altered the marine conditions of living organisms, but the dimension of the impact remains unclear. The OOCS multisensor coordinated monitoring has been specifically designed to address this issue, thus contributing to better understand the present environmental fluctuations and to provide a sound basis for a more accurate marine forecast system., The OOCS is supported by the Spanish Ministry of Science and Innovation project “Observation, analysis and modelling of the Mediterranean Sea—OAMMS” CTM2008-03983.Part of this research was funded within the framework of the National Research Project RITFIM (CTM2010-16274). Jacopo Aguzzi is a Postdoctoral Fellow of the Ramón y Cajal Program (MICINN).

De febrero de 1997 a febrero de 1998, se recolectaron mensualmente muestras aleatorias del molusco Atrina maura en el sistema lagunar Corralero-Alotengo, Oaxaca, México. Se extrajeron las partes blandas para lavarlas in situ y fijarlas en solución Davison. En el laboratorio se pesaron para obtener los índices gonadosomático (IGS) y de rendimiento muscular (IRM), y mediante cortes histológico de las gónadas se caracterizó el ciclo reproductivo. Esta población se reproduce casi todo el año, con dos periodos reproductivos importantes: uno de abril a julio y otro de octubre a noviembre, y una sola época de reposo, en agosto y septiembre. El ciclo reproductivo tiene una relación directa con el IGS e inversa con el IRM. Hay evidencias de una relación estrecha de las época de desove y postdesove con la temperatura del agua (R = 0.991, p 0.002). Las hembras predominaron casi todo el año, aunque esta proporción solo tuvo diferencias estadísticamente significativas en noviembre (X²: p= 0.05)Reproductive cycle of the mollusk Atrina maura (Pterioidea: Pinnidae) in a coastal lagoon system of the Mexican South Pacific. From February 1997 to February 1998, random samples of the mollusk Atrina maura were collected on a monthly basis from the Corralero-Alotengo lagoon system, Oaxaca, Mexico. The soft parts were separated from the valve, washed in situ, and placed in a Davison solution. The gonadosomatic index (GSI) and the muscle yield index (MYI) were measured, and the reproductive cycle was characterized by histological cuts. A. maura has two important reproductive periods, one from April to July and another from October to November; there is a resting period from August to September. The reproductive cycle has a direct relationship with the GSI and a reverse relationship with the MYI. There was evidence of a close relationship of the spawning and post-spawning periods with the water temperature (R = 0.991, p = 0.002). Females dominate numerically throughout the year, but the difference is significant (X²: p= 0.05) only in November. Rev. Biol. Trop. 55 (3-4): 839-852. Epub 2007 December, 28.